Support ADJUST_DISTRIBUTION_ONTHEFLY to set distribution in binary builds
Support ADJUST_DISTRIBUTION_ONTHEFLY to set distribution in binary builds

This is useful when you're building for different distributions
using the same source package and want to avoid that the changes
file is the same for all of the builds.

See https://github.com/mika/jenkins-debian-glue/pull/112 for the according
discussion.

Thanks: Yurii Vlasenko for reporting and feedback

n054/jenkins-debian-glue,wikimedia/operations-debs-jenkins-debian-glue,kartikm/jenkins-debian-glue,hetznerZA/jenkins-debian-glue,mika/jenkins-debian-glue,jbfavre/jenkins-debian-glue,jbfavre/jenkins-debian-glue,bmiklautz/jenkins-debian-glue,kartikm/jenkins-debian-glue,linuxmaniac/jenkins-debian-glue,mika/jenkins-debian-glue,webtrekk-kane/jenkins-debian-glue,webtrekk-kane/jenkins-debian-glue,tonin/jenkins-debian-glue,wikimedia/operations-debs-jenkins-debian-glue,hetznerZA/jenkins-debian-glue,hashar/jenkins-debian-glue,cclausen/jenkins-debian-glue,bmiklautz/jenkins-debian-glue,hashar/jenkins-debian-glue,linuxmaniac/jenkins-debian-glue,tonin/jenkins-debian-glue,cclausen/jenkins-debian-glue,n054/jenkins-debian-glue